Figure 1.

Basal production of PGE₂ in the colon is regulated by COX-2 and mPGES-1 with significant contribution from cells of the adaptive immune system. (A) Colon explants from WT (blue), mPGES-1^−/− (red), Rag1^−/− (black) or Rag1^−/− × mPGES-1^−/− (red/black) mice were cultured for 12 h and their supernatants were analyzed for basal PGE₂ production. The specific COX2 inhibitor NS-398 was added to evaluate the differential contribution of COX2 and COX1 to the PGH₂ pool prior to PGE₂ biosynthesis. (B) PGE₂ production in colon explants from untreated WT mice (“Untreated,” blue circles) or Rag1^−/− mice undergoing WT Teff cell-driven colitis at week 10 post-transfer (“Colitic,” black squares). ** indicates a P value < 0.05 using a 2-tailed heteroscedastic Student's T-test. (C) Immunohistochemistry of COX2 (upper row) and mPGES-1 (lower row) in the colon of mice that transferred with WT Teff cells (CD4⁺CD25⁻CD45RB^hi). Scale bar is 100 μm long. Arrowheads 1 and 2 point to localization within the LP, while arrowhead 3 indicates localization in the brush border. ** Significant at P < 0.05 and *** at P < 0.01 in a one-way ANOVA with Welch's correction.